Routing Power In A Power System

ABSTRACT

A power system comprising one or more power generators and a combiner. The system may be electrically connected to or include one or more loads. The combiner may have input terminals that are coupled to outputs of the power generators. The combiner may also have output terminals that are coupled to input(s) of the one or more loads. The power generators may be configured to transfer harvested power to the combiner, and the combiner may be configured to transfer the harvested power to the one or more loads.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 17/488,462, filed Sep. 29, 2021, which is a continuation ofU.S. patent application Ser. No. 15/991,074, filed May 29, 2018, nowU.S. Pat. No. 11,171,491, which claims priority to U.S. ProvisionalPatent Application Ser. No. 62/512,325, filed May 30, 2017, all of whichare hereby incorporated by reference in their entireties.

BACKGROUND

Power generators, especially renewable power generators such asphotovoltaic panels, may perform variably under varying conditions suchas temperature, light exposure, weather conditions such as rain, snow,wind, etc. A power system may include a number of power generators ofdifferent types, such as wind turbines, photovoltaic panels,hydroelectric systems, etc. In some systems, power generators ofdifferent types and/or operating under different conditions may beconnected to a common load. Because of the different types of powergenerators and/or the operation of power generators under differentconditions, voltage and/or current mismatches may develop between thepower generators. When combining the power generators to power a commonload, there may be power loss due to the mismatches between the powergenerators.

SUMMARY

The following is a short summary of some of the inventive concepts forillustrative purposes only, is not intended to limit or constrain theinventions and examples in the detailed description, and is not intendedto identify key or essential features. One skilled in the art willrecognize other novel combinations and features from the detaileddescription.

In illustrative embodiments a power system may include a combiner andone or more power generators. The power system may also be electricallyconnected to or include one or more loads. The combiner's inputterminals may be coupled to the outputs of the power generators. Thecombiner's output terminals may be coupled to the one or more loads'inputs. The power generators may be configured to transfer harvestedpower to the combiner, and the combiner may be configured to transferthe harvested power to the loads.

In illustrative embodiments there may be a power converter between thecombiner and the load. The power converter may be configured to convertDC power or AC power, depending on the power generators and the loadconfigured to receive the harvested power. The power converter may houseand/or be electrically coupled to a power device. In some embodiments,the power device may perform power point tracking (PPT) on the powergenerators.

In illustrative embodiments, power devices may be positioned between thepower generators and the combiner, such that the power generators'outputs may couple to the power devices' inputs, and the power devices'outputs may couple to the combiner's input terminals. The power devicesmay be configured to perform PPT on the power generators that arecoupled to them. The combiner may be configured to match the differentpower device outputs in order to combine the power harvested from thenumber of power generators and transfer the power to a load or a powerconverter.

In illustrative embodiments, power devices may be coupled to differentsections in one or more of the power generators. The power devices maybe configured to convert the harvested power to an output power having aset or maximal value for an electrical parameter, for example, a setvoltage or a set current. The power devices may be configured to performPPT on their respective sections of the power generators.

In illustrative embodiments, the combiner may have multiple switchescoupled to input terminals. The combiner may have a controllerconfigured to control the state (e.g. ON, OFF) of the switches. Thecombiner may have multiple output terminals. The controller may beconfigured to change the state of the switches depending on electricalparameter values at one or more input terminals. The input terminals maybe connected in parallel, in series or in a combination of both paralleland series. In some embodiments, the controller may determine to reducepower drawn from a power source, for example, by shorting ordisconnecting one or more of the input terminals. The values of theelectrical parameters (e.g. voltage, current, power) and thermalparameters (e.g. temperatures) at each one of the input terminals may bemeasured and provided to the controller by sensors placed at the inputterminals to the combiner. The output terminals of the combiner may beconnected to switches controlled by a controller. The controller mayconnect the output switches in series, parallel, a combination of bothparallel and series configuration and/or short or disconnect one or moreoutput terminals. The configuration may also depend on the values of theelectrical parameters that the load or power converter are set toreceive.

In illustrative embodiments, the power system may have a safetymechanism. In some embodiments, the safety mechanism may be configuredto signal and/or communicate with the power converter. In someembodiments, the safety mechanism may be configured to signal and/orcommunicate with the combiner. The safety mechanism may be configured tosend a first signal such as a “go into safe mode” signal. The “go intosafe mode” signal may be sent using a power line communication (PLC)device, wireless communication device, acoustic communication device,cellular device, etc. In some embodiments, the safety mechanism mayinclude a communication device configured to send a second signal, suchas a “keep alive” signal, as long as system operating conditions enablecontinued and safe power production, and configured to cease sending the“keep alive” signal in the presence of one or more certain conditions,such as a potentially unsafe condition (e.g. excess voltage, current,power, temperature, etc.)

In some embodiments, the power system may be coupled to a userinterface. The user interface may be configured to display values ofparameters, such as electrical parameters in the power generators, powerdevices, the combiner, the power converter, and/or the load. The userinterface may display different status reports of different componentsin the power system, for example: temperature, power supply parameters,and/or results of a comparison between parameters of the powergenerators. The user interface may be used to control components of thepower system. This may allow, for example, a user to connect and/ordisconnect the power devices and/or power converters, disconnect acertain power generator from the combiner, set an output voltage fromthe combiner, set an output current from the combiner, etc.

According to still further embodiments and aspects, a combiner maycomprise a plurality of input terminals configured to receive power, aplurality of switches coupled to the plurality of input terminals andconfigured to electrically couple the plurality of input terminals, anda plurality of output terminals configured to output the power receivedby the plurality of input terminals. The combiner may further comprise,in any combination or subcombination, one or more of the following: acontroller configured to switch the plurality of switches coupled to theplurality of input terminals; and/or switches coupled to the pluralityof output terminals and configured to electrically couple the pluralityof output terminals. The plurality of switches may be configured toelectrically couple the plurality of input terminals in parallel and/orseries. The plurality of input terminals may be configured to receivepower from one or more power devices. The power devices may be coupledto a power generator. The power devices may be configured to receivepower from one or more coupled power generator, and/or configured tofind and apply an operating point for the power generator(s). Theoperating point may comprise setting a voltage and/or current of thepower generator(s).

According to yet further embodiments and aspects, a system may compriseone or more power generators configured to output power, and a combinerthat may comprise a plurality of input terminals and a plurality ofoutput terminals. The plurality of input terminals may be configured toreceive the power output from the one or more power generators and theplurality of output terminals may be configured to output the power. Thesystem may be electrically connected to or include a load configured toreceive the power output from the combiner. The system may furthercomprise, in any combination or subcombination, one or more of thefollowing: one or more power devices, which may comprise a plurality ofinput terminals coupled to the one or more power generators, and aplurality of output terminals, and may be configured to convert power; apower converter coupled between the output of the combiner and the load;and/or a safety mechanism configured to signal the power converterand/or the combiner to go into “safe mode”. The power converter maycomprise a plurality of input terminals and a plurality of outputterminals, wherein the plurality of input terminals to the powerconverter are configured to electrically couple to the output terminalsof the combiner, and wherein the plurality of output terminals of thepower converter are configured to electrically couple to the load. The“safe mode” may comprise lowering the voltage at the input of the powerconverter.

According to still further embodiments and aspects, a system maycomprise a plurality of power generating devices that comprise a firstgroup of power generating devices and a second group of power generatingdevices; one or more optimizers connected to the plurality of powergenerating devices; and a combining device connected to the one or moreoptimizers. The combining device may be configured as described in otherembodiments and aspects herein and/or may comprise one or moreprocessors, and memory storing machine readable instructions. Whenexecuted by the one or more processors, the instructions may cause theone or more processors to: measure, using one or more sensors, aparameter of the first group of power generating devices; measure, usingthe one or more sensors, a parameter of the second group of powergenerating devices; measure, using the one or more sensors, a combinedparameter of the first group and the second group; and based on theparameter of the first group, the parameter of the second group, and thecombined parameter, deactivate the first group of power generatingdevices, deactivate the second group of power generating devices, ordeactivate the first group of power generating devices and the secondgroup of power generating devices. The parameter of the first group maycomprise a measured voltage, a measured temperature, a measured current,or a measured voltage on the first group. The parameter of the secondgroup may comprise a measured voltage on the second group, and thecombined parameter may comprise a measured voltage on the first groupand the second group. The instructions may further cause the one or moreprocessors to compare the parameter of the first group of powergenerating devices to a ground parameter or a neutral parameter. Amethod is further provided to perform the steps dictated by themachine-readable instructions.

According to still further embodiments and aspects, a system maycomprise a plurality of power generating devices that comprise a firstgroup of power generating devices and a second group of power generatingdevices; one or more optimizers connected to the plurality of powergenerating devices; and a combining device connected to the one or moreoptimizers. The combining device may be configured as described in otherembodiments and aspects herein and/or may comprise one or moreprocessors, and memory storing machine readable instructions. Whenexecuted by the one or more processors, the instructions may cause theone or more processors to measure, using one or more sensors, aparameter of the first group of power generating devices; measure, usingthe one or more sensors, a parameter of the second group of powergenerating devices; measure, using the one or more sensors, a combinedparameter of the first group and the second group; and based on theparameter of the first group, the parameter of the second group, and thecombined parameter of the first group and the second group, transmit aninstruction, to the one or more optimizers, to control a voltage on thefirst group, control a voltage on the second group, or control a voltageon the first group and the second group. The instruction that istransmitted may comprise an instruction to modify the voltage or toprevent the voltage from rising. A method is further provided to performthe steps dictated by the machine-readable instructions.

According to still further embodiments and aspects, a system maycomprise a plurality of power generating devices that comprise a firstgroup of power generating devices and a second group of power generatingdevices; one or more optimizers connected to the plurality of powergenerating devices; and a combining device connected to the one or moreoptimizers. The combining device may be configured as described in otherembodiments and aspects herein and/or may comprise one or moreprocessors, and memory storing machine readable instructions. Whenexecuted by the one or more processors, the instructions may cause theone or more processors to measure, using one or more sensors, aparameter of the first group of power generating devices; measure, usingthe one or more sensors, a parameter of the second group of powergenerating devices; and based on the parameter of the first group andthe parameter of the second group, deactivate the first group of powergenerating devices, deactivate the second group of power generatingdevices, or deactivate the first group of power generating devices andthe second group of power generating devices. A method is furtherprovided to perform the steps dictated by the machine-readableinstructions.

Methods are described for electrically coupling the input terminals ofthe combiner in a preferred configuration. The input terminals to thecombiner may be electrically coupled in series or in parallel, and incertain scenarios there may be a different configuration of couplingwhich may be more efficient with regard to the amount of powertransferred to the outputs of the combiner. A method of electricallycoupling the input terminals in a certain configuration may be carriedout by a controller placed in the combiner or coupled to the combiner.The controller may differentiate between two or more scenarios, such asa first scenario and a second scenario. For example, the first scenariomay be an output voltage on the output terminals of the combinerdetermined by a load or an inverter, and the second scenario may bewhere the output terminals voltage is not determined but ratherdependent on the configuration of the input terminals to the combiner.In the first scenario, where the voltage on the output terminals isdetermined by a load or an inverter, the first step may include findingand/or setting an operating point for each one of the power generatorscoupled to the input terminals of the combiner.

In the first scenario and in the second scenario the next step may bematching voltages and/or currents between the input terminals of thecombiner. Matching voltages and currents may include connecting certaininput terminals with similar current values in series, and connectingcertain input terminals in parallel with even voltage values.

The method of matching voltages and currents may include the followingsteps. At an initial stage, the controller may determine that there are“n” pairs of inputs to the combiner, coupled to power generators. Thecontroller may divide the “n” pairs into “k” groups of inputs. Eachgroup of the “k” groups that has more than “k” inputs is divided into“m” sub-groups. This step is repeated until each group and sub-group has“k” or less pairs of inputs. The next step may include selecting aconnectivity configuration for each one of the “k” or less pairs ofinputs, and electrically coupling the “k” or less input pairs togetheraccording to the selected configuration. After the pairs of inputs ofthe sub-groups are connected, the next step may include selecting aconnectivity configuration of the sub-groups and groups and electricallycoupling them accordingly. When all inputs, sub-groups and groups areelectrically coupled, the matching of the voltage and current isfinished.

The method of selecting a connectivity configuration and electricallycoupling input terminals, or groups of input terminals may includeseveral steps. The first step may include electrically coupling theinput terminals or groups of input terminals in parallel and measuringthe values of the combined electrical parameters (e.g. voltage andcurrent). A step may include electrically coupling the input terminalsor groups of input terminals in series and measuring the values of thecombined electrical parameters. After the measurements of bothconfigurations are available, the controller may compare themeasurements and, at a later step, the controller may electricallycouple the input terminals or groups of input terminals according thecomparison of the measurements.

According to still further embodiments and aspects, methods aredescribed that comprise receiving power from one or more powergenerators, transferring the received power from a plurality of inputsto a plurality of outputs, and outputting the power to a load. Themethods may further comprise various steps in any combination orsubcombination, such as sensing electrical parameters at the pluralityof input terminals; electrically coupling the plurality of inputterminals in a parallel configuration, series configuration and/or acombined configuration; shorting one or more of the plurality of inputterminals; and/or receiving a go into “safe mode” signal, where the“safe mode” may comprise, for example, disconnecting one or more of theplurality of input terminals and/out output terminals.

Systems and apparatuses are also described for performing all of theabove methods and other methods.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects, and advantages of the presentdisclosure will become better understood with regard to the followingdescription, claims, and drawings. The present disclosure is illustratedby way of example, and not limited by, the accompanying figures.

FIG. 1 is a part schematic, part block-diagram, of an example powersystem configuration, according to various aspects of the presentdisclosure.

FIG. 2 is a part schematic, part block-diagram, of an example powersystem configuration including power devices between power generatorsand a combiner, according to various aspects of the present disclosure.

FIG. 2A is a block diagram of an example power device, according tovarious aspects of the present disclosure.

FIG. 3 is a part schematic, part block-diagram of an example powersystem configuration including power devices coupled to or incorporatedwithin power generators, according to various aspects of the presentdisclosure.

FIG. 4 is a part schematic, part block-diagram, of an example combinerincluding sensors coupled to the input terminals as well as the outputterminals, according to various aspects of the present disclosure.

FIG. 4A is a part schematic, part block diagram, of an example combinerincluding switches configured to electrically couple or uncouple inputterminals of the combiner and couple input terminals to output terminalsof the combiner, according to various aspects of the present disclosure.

FIG. 5A is a part schematic, part block-diagram, of an example combinerand its input terminals electrically coupled in a series configuration,according to various aspects of the present disclosure.

FIG. 5B is a part schematic, part block-diagram, of an example combinerand its input terminals electrically coupled in a parallelconfiguration, according to various aspects of the present disclosure.

FIG. 5C is a part schematic, part block-diagram, of an example combinerand its input terminals electrically coupled in a combination of bothparallel and series configurations, according to various aspects of thepresent disclosure.

FIG. 5D is a part schematic, part block-diagram, of an example combinerand its input terminals electrically coupled in a combination of bothparallel and series configuration as well as a shorted pair of inputterminals, according to various aspects of the present disclosure.

FIG. 5E is a part schematic, part block diagram, of an example combinerand its input terminals coupled to a power generator where the inputterminals are coupled in a configuration set to divide the powergenerator in to more than one string, according to various aspects ofthe present disclosure.

FIG. 5F is a block diagram of an example power system including a powerstring, combiner and a load, according to various aspects of the presentdisclosure.

FIG. 6 is a part schematic, part block-diagram, of an example powersystem configuration including a user interface and a safety mechanism,according to various aspects of the present disclosure.

FIG. 7A is a flowchart showing an example method for transferring powerfrom a combiner's input terminals to a combiner's output terminals,according to various aspects of the present disclosure.

FIG. 7B is a flowchart showing an example method for determining andelectrically coupling a combiner's input terminals in a parallel, seriesor combined configuration, according to various aspects of the presentdisclosure.

FIG. 7C is a flowchart showing an example method for determining andelectrically coupling a sub-group of a combiner's input terminals in aparallel, series or combined configuration, according to various aspectsof the present disclosure.

DETAILED DESCRIPTION

In the following description of various illustrative embodiments,reference is made to the accompanying drawings, which form a parthereof, and in which are shown, by way of illustration, variousembodiments in which aspects of the disclosure may be practiced. It isto be understood that other embodiments may be utilized and structuraland functional modifications may be made, without departing from thescope of the present disclosure.

Reference is now made to FIG. 1 , which shows a power system 100according to illustrative embodiments. Power system 100 may comprise oneor more power generators 101 a-101 n, where each power generator ofpower generators 101 a-101 n may be a photovoltaic (PV) generator, windturbine, hydro-turbine, fuel cell, battery, and/or supercapacitor, usedas a power source. In some embodiments, where power generators 101 a-101n are PV generators, power generators 101 a-101 n may be a PV cell, astring of PV cells connected in a parallel configuration, a string of PVcells connected in a series configuration, a string of PV cellsconnected in a combination of parallel and series configuration(“combination of parallel and series configuration” is referred toherein as a “combined configuration”), one or more substrings of PVcells, a photovoltaic panel, a string of photovoltaic panels in aparallel configuration, a string of photovoltaic panels in a seriesconfiguration, and/or a string of photovoltaic panels in a combinedconfiguration. Power system 100 may comprise a system power device 103.

In some embodiments, system power device 103 may comprise a DC/ACinverter and may output alternating current (AC) power to an electricalgrid, where the electrical grid may be a network for deliveringelectricity from a supplier to a consumer, a home, or otherdestinations. In some embodiments, system power device 103 may comprisea combiner box, transformer and/or safety disconnect circuit. Forexample, system power device 103 may comprise a DC combiner box forreceiving DC power from a plurality of power generating strings andoutputting the combined DC power. In some embodiments, system powerdevice 103 may comprise a fuse coupled to each string for overcurrentprotection, and/or one or more disconnect switches for disconnecting oneor more power generating strings. In some embodiments, system powerdevice 103 may comprise or be coupled to a control device and/or acommunication device for controlling or communicating with PV powerdevices (such as power devices 202 a-n of FIG. 2 ). For example, systempower device 103 may comprise a control device such as a microprocessor,Digital Signal Processor (DSP) and/or a Field Programmable Gate Array(FPGA) configured to control the operation of system power device 103.System power device 103 may further comprise a communication device(e.g. a Power Line Communication circuit and/or a wireless transceiver)configured to communicate with linked communication devices included inPV power devices. In some embodiments, system power device 103 maycomprise both a control device and a communication device, the controldevice configured to determine desirable modes of operation for PV powerdevices (e.g. power devices 202 of FIG. 2 ), and the communicationdevice configured to transmit operational commands and receive reportsfrom communication devices included in the PV power devices.

System power device 103 may be a DC/DC power converter and/or a DC/ACpower converter. In some embodiments, system power device 103 may applypower point tracking (PPT) to power generators 101 a-101 n. PPT mayinclude determining and applying an operating point best fit for thepower system 100. An operating point includes setting a parameter suchas a voltage and/or a current on one or more, or even all, of powergenerators 101 a-101 n. An operating point best fit for power system 100may include harvesting maximum power from power generators 101 a-101 n,harvesting maximum power that system power device 103 is able toconvert, etc. PPT may be done, for example, using various methods suchas “perturb and observe”, impedance matching and/or lookup tables.Lookup tables may be indexed according to various parameters, forexample, voltage, current, and/or temperature. For example, for a giventemperature, a lookup table may indicate a voltage and/or current bestfit for power system 100. Another example for PPT may be dynamic PPT.Dynamic PPT may include “perturb and observe” or an impedance matchingmethod. For example dynamic PPT may comprise changing the voltage and/orcurrent, sensing and measuring the respective current and/or voltageand, according to the power value of both the set voltage and/or currentand the measured current and/or voltage, choosing a power point fit forpower system 100. System power device 103 may comprise a DC/DC converterand/or a DC/AC converter. Where system power device 103 comprises both aDC/DC converter and a DC/AC converter, system power device 103 may beconfigured to convert DC to DC before converting DC to AC. For example,system power device 103 may set a voltage of V=400V_(DC) (e.g., fordrawing increased or maximum power from power generators 101 a-101 n) atthe input of system power device 103, and system power device 103 may beconfigured to convert DC power to AC power at a voltage of V=700V_(DC).For example, system power device 103 may convert power with a DC voltageof 400V_(DC) to power with a DC voltage of 700V_(DC) before convertingDC power to AC power.

In some embodiments, power system 100 may comprise a combiner 102. Powersystem 100 may have more output terminals from power generators 101a-101 n than input terminals to system power device 103. Combiner 102may be an intermediary between power generators 101 a-101 n and systempower device 103 by electrically coupling power generators 101 a-101 nat the input to the combiner 102, and outputting power received frompower generators 101 a-101 n to system power device 103 through outputterminals of the combiner 102, which may correspond to the number ofinputs to system power device 103. Combiner 102 may electrically couplepower generators 101 a-101 n in parallel, in series or in a combinedconfiguration. For example, power converter 103 may have two inputterminals, while power system 100 may have six power generators 101a-101 f wherein each one of power generators 101 a-101 f may have a pairof output terminals. Combiner 102 may electrically couple powergenerators 101 a-101 f in series, parallel or a combined configuration,and output the power via two output terminals. Combiner 102, or anyportion thereof, may be placed independently in power system 100 or maybe housed in or mounted on system power device 103. For example,portions of the combiner 102 may be separate from the system powerdevice 103, and portions of the combiner 102 may be integrated in,housed in, or mounted on system power device 103.

Reference is now made to FIG. 2 which illustrates a power system 200according to illustrative embodiments. Power system 200 may comprisepower generators 201 a-201 n, which may be the same or similar to powergenerators 101 a-101 n of FIG. 1 . Power system 200 may comprise systempower device 204, which may comprise a DC/AC power converter and/orDC/DC power converter. Power devices 202 a-202 n may be coupled to oneor more of power generators 201 a-201 n. Power devices 202 a-202 n maycomprise a DC/DC power converter and/or a DC/AC power converter. Powerdevices 202 a-202 n may perform PPT on corresponding power generators ofpower generators 201 a-201 n coupled to power devices 202 a-202 n. Forexample, power device 202 a may be coupled to power generator 201 a, andpower device 202 a may perform PPT on power generator 201 a. In anotherexample, power device 202 a may be coupled to two or more powergenerators, and may perform PPT on the two or more power generators.Power system 200 may comprise a combiner 203. Combiner 203 may be thesame or similar to combiner 102 of FIG. 1 . Combiner 203 may have one ormore input terminals, which may be configured to electrically couple topower devices 202 a-202 n and/or power generators 201 a-201 n. Powerdevices 202 a-202 n may be configured to output power with the samevoltage and/or current level as each of the other power devices 202a-202 n. Combiner 203 may electrically couple the input terminalscoupled to power devices 202 a-202 n in series, parallel or a combinedconfiguration. Combiner 203 may be configured to output the powerreceived from power generators 201 a-201 n, via the power devices 202a-202 n, to system power device 204.

Reference is now made to FIG. 2A, which illustrates circuitry that maybe found in a power device such as power device 202, according to anillustrative embodiment. Power module 202 may be similar to or the sameas power devices 202 a-202 n shown in FIG. 2A. In some embodiments,power device 202 may comprise power circuit 205. Power circuit 205 maycomprise a direct current to direct current (DC/DC) converter, such as aBuck, Boost, Buck/Boost, Buck+Boost, Cuk, Flyback, and/or forwardconverter. In some embodiments, power circuit 205 may comprise a directcurrent to alternating current (DC/AC) converter (also known as aninverter), such as a micro-inverter. Power circuit 205 may have twoinput terminals and two output terminals, which may be the same as theinput terminals and output terminals of power device 202. In someembodiments, the two input terminals of power device 202 may be directlycoupled to the two output terminals of power device 202, so that powerdevice 202 functions without power conversion (i.e. power circuit 205might not be included in the system or might not perform powerconversion). In some embodiments, power circuit 205 may comprise aswitch to disconnect the input terminals from the output terminals. Insome embodiments, power device 202 may comprise Maximum Power PointTracking (MPPT) circuit 206, which may be configured to extractincreased power from a power source the power device 202 is coupled to.In some embodiments, power circuit 205 may comprise MPPT functionality.In some embodiments, MPPT circuit 206 may implement impedance matchingalgorithms to extract increased power from a power source the powerdevice 202 is coupled to. Power device 202 may further comprisecontroller 207 which may be a microprocessor, Digital Signal Processor(DSP), Application-Specific Integrated Circuit (ASIC) and/or a FieldProgrammable Gate Array (FPGA).

Referring still to FIG. 2A, controller 207 may control and/orcommunicate with other elements of power device 202 over common bus 210.In some embodiments, power device 202 may comprise circuitry and/orsensors/sensor interfaces 208 configured to measure one or moreparameters directly or receive one or more measured parameters fromconnected sensor(s) and/or sensor interface(s) configured to measure oneor more parameters that may be, for example, on or near the powersource. The sensors 208 may measure, among other parameters, the voltageand/or current output by the power source, and/or the power output bythe power source. In some embodiments, the power source may be aphotovoltaic (PV) generator comprising PV cells, and a sensor unit(e.g., one or more sensors and/or sensor interfaces 208) may directlymeasure or receive measurements of the irradiance received by the PVcells, and/or the temperature on or near the PV generator.

Referring still to FIG. 2A, in some embodiments power device 202 maycomprise communication interface 209, which may be configured totransmit and/or receive data and/or commands to/from other devices.Communication interface 209 may communicate using Power LineCommunication (PLC) technology, which may enable data transmission overexisting power cables. Communication interface 209 may communicate usingwireless technologies such as ZigBee™, Wi-Fi, cellular communication, orother wireless methods. Communication interface 209 may also comprise ameans for opto-electronic communication, which may comprise opticalfibers to convey data and/or commands from other devices.

In some embodiments, power device 202 may comprise memory device 211,which may comprise one or more physical memories such as memory chips.The memory device 211 may store measurements taken by sensor(s)/sensorinterfaces 208. The memory device 211 may store code, operationalprotocols or other operating information. Memory device 211 may be orotherwise include Flash, Electrically Erasable Programmable Read-OnlyMemory (EEPROM), Random Access Memory (RAM), Solid State Devices (SSD),and/or other types of appropriate memory devices.

Referring still to FIG. 2A, in some embodiments, power device 202 maycomprise one or more safety devices 212 (e.g. fuses, circuit breakersand Residual Current Detectors). Safety devices 212 may each be passiveor active. For example, safety devices 212 may comprise one or morepassive fuses disposed within power device 202. The one or more passivefuses may be designed to melt when a certain amount of current flowsthrough a fuse, which may cause part of power device 202 to disconnect,thereby limiting damage to the power device 202. In some embodiments,safety devices 212 may comprise active disconnect switches, which may beconfigured to receive commands from a controller (e.g. controller 207,or an external controller) to disconnect portions of power device 202.The active disconnect switches may be configured to disconnect portionsof power device 202 in response to a measurement measured by a sensor(e.g. a measurement measured or obtained by sensors/sensor interfaces208). In some embodiments, power device 202 may comprise auxiliary powercircuit 213, which may be configured to receive power from a powersource coupled to power device 202, and output power suitable foroperating other circuitry components (e.g., controller 207,communication interface 209, etc.). Communication, electrical couplingand/or data-sharing between the various components of power device 202may be carried out over common bus 210.

Referring still to FIG. 2A, in some embodiments, power device 202 maycomprise one or more bypass units Q9 a and/or Q9 b, which may be coupledbetween the inputs of power circuit 205 and/or between the outputs ofpower circuit 205. Bypass units Q9 a-b and/or power circuit 205 may beor otherwise include a junction box to terminate power lines or toprovide a safety feature such as fuses or residual current devices.Bypass units Q9 a-b may also be isolation switches, for example. Bypassunits Q9 a-b may be controlled by controller 207. If an unsafe conditionis detected, controller 207 may set bypass unit Q9 a and/or bypass unitQ9 b to ON, thereby short-circuiting the input and/or output of powercircuit 205. In a case in which a power generators 201 a-201 n arephotovoltaic (PV) generators, each PV generator may have an open-circuitvoltage at the generator output terminals. When bypass unit Q9 a is ON,a PV generator may be short-circuited, to provide a voltage ofapproximately zero to power circuit 205. Bypass Units Q9 a-b may beoperated to maintain a safe voltage at the output terminals of powerdevice 202. For example, bypass unit Q9 b may short-circuit the outputterminals, to provide an output voltage of about 0V, while bypass unitQ9 a may be OFF, allowing a PV generator to maintain a generator outputvoltage which may be provided to auxiliary power circuit 213. This modeof operation may allow continuous power supply to system controldevices, as well as provide backup mechanisms for maintaining a safevoltage.

Sensor(s) 208, which may be operatively attached to controller 207, maycomprise analog to digital converters (not shown) that may be connectedto sensors. The sensors may be configured to detect electricalparameters, such as current, of power device 202. The sensors may beconfigured to detect electrical parameters of power circuit 205 andpower generators 201 a-201 n. Sensor/sensor interface 208 may comprisean energy gauge to count coulombs (amperes per second), for example wheneither charging or discharging a battery. The sensors may be locatedand/or integrated inside power circuit 205. The sensors may be spatiallylocated in the vicinity of power device 202. Similarly, a sensor may bespatially located in the vicinity of power generators 201 a-201 n.Additional sensors may be added and configured to sense, for example,temperature, humidity, and/or luminance.

Reference is now made to FIG. 3 , which illustrates a power system 300according to illustrative embodiments. Power system 300 may comprisepower generators 301 a-301 n which may be the same or similar to powergenerators 101 a-101 n of FIG. 1 . Power generators 301 a-301 n mayoutput power to a combiner 302. Combiner 302 may transfer the outputpower from power generators 301 a-301 n to a system power device 303.System power device 303 may have one or more input terminals coupled toone or more output terminals of combiner 302. In some embodiments, someor all parts of power generators 301 a-301 n may be coupled to powerdevices, and the power devices may be configured to perform PPT anddetermine a preferred operating point of the corresponding powergenerators 301 a-301 n. Power devices coupled to power generator partsof power generators 301 a-301 n may output harvested power at a certainvoltage and/or current level. Combiner 302 may receive power from powergenerators 301 a-301 n and, depending on the voltage and current levelsat the pairs of input terminals of combiner 302, may electrically couplethe pairs of input terminals to combiner 203 in a series configuration,parallel configuration, or a combined configuration.

Reference is now made to FIG. 4 , which illustrates a combiner 400according to illustrative embodiments. Combiner 400 may have inputterminals 401 a-401 n coupled to switches 4Sa-4Sn. Switches 4Sa-4Sn maycomprise, for example, one or more of the following: ametal-oxide-semiconductor field-effect transistor (MOSFET), aninsulated-gate bipolar transistor (IGBT), a Bipolar Junction Transistor(BJT), and/or relay switches. One or more of input terminals 401 a-401 nmay be electrically coupled to a power source such as power generators101 a-101 n of FIG. 1 . Combiner 400 may comprise a controller 402,which may be configured to operate switches 4Sa-4Sn. Controller 402 maybe, for example, a digital signal processor (DSP), microcontroller unit(MCU), a field-programmable gate array (FPGA), an application-specificintegrated circuit (ASIC), an analog control circuit, etc. Combiner 400may output power at output terminals 403 a-403 m. In some embodiments,output terminals 403 a-403 m may output power to one or more powerconverters. For example, combiner 400 may output power to three powerconverters, each power converter having a pair of input terminals, andcorrespondingly, combiner 400 may have six output terminals 403 a-403 f.Output terminals 403 a-403 m may be electrically coupled in a parallel,series or a combined (e.g. series and parallel) configuration. In someembodiments, controller 402 may electrically couple one or more of inputterminals 401 a-401 d to one or more of output terminals 403 a-403 m andmay short one or more of input terminals 401 a-401 n.

In some embodiments, combiner 400 may have sensors/sensor interfaces 4a-4 n, configured to sense electrical parameters of power flowingthrough input terminals 401 a-401 n. Sensors/sensor interfaces 4 a-4 nmay be configured to sense one or more parameters, for example, voltage,current, heat and connection status of the power generators to inputterminals 401 a-401 n. In some embodiments sensors/sensor interfaces 4a-4 n may sense parameters on input terminals 401 a-401 n in relation orcompared to a ground or neutral reference point, or between two inputterminals (e.g. voltage between input terminal 401 a and input terminal401 g). Sensors/sensor interfaces 4 a-4 n may be coupled to controller402 and controller 402 may be configured to receive values sensed bysensors/sensor interfaces 4 a-4 n. In some embodiments, output terminals403 a-403 m may be coupled with output sensors/sensor interfaces 404a-404 m. Output sensors/sensor interfaces 404 a-404 m may be the same orsimilar to sensors/sensor interfaces 4 a-4 n. Controller 402 may beconfigured to open and close switches 4Sa-4Sn according to values sensedby sensors/sensor interfaces 4 a-4 n and/or output sensors/sensorinterfaces 404 a-404 m. Depending on the operation of switches 4Sa-4Snat input terminals 401 a-401 n, and the electrical configuration ofinput terminals 401 a-401 n, combiner 400 may transfer power from inputterminals 401 a-401 n to output terminals 403 a-403 m.

Reference is now made to FIG. 4A, which shows an example of animplementation of combiner 400 according to illustrative embodiments.Combiner 400 may comprise input terminals 401 a-401 d coupled to powergenerators. Switches S1-S7 may be MOSFETs coupled to controller 402,where controller 402 may be coupled to the gates of switches S1-S7 andconfigured to control switches S1-S7. In an embodiment where switchesS2, S4 and S7 are ON and switches S1, S3, S5 and S6 are OFF, inputterminals 401 a-401 d may be electrically coupled in a seriesconfiguration, and power may transfer from input terminals 401 a-401 dto output terminals 403 a-403 b. In an embodiment where switches S2, S3,S5 and S7 are ON and switches S1, S4 and S6 are OFF, input terminals 401a-401 d may be electrically coupled in a parallel configuration, andpower may transfer from input terminals 401 a-401 d to output terminals403 a-403 b. In an embodiment where switches S1 and S6 are ON, inputterminals 401 a-401 d may be shorted, and power might not transfer frominput terminals 401 a-401 d to any of the output terminals 403 a-403 b.In an embodiment where switches S1-S7 are OFF, input terminals 401 a-401d may be uncoupled from combiner 400, and power might not transfer frominput terminals 401 a-401 d to output terminals 403 a-403 b.

Reference is now made to FIG. 5A, which shows a combiner 500 in a firstmode of operation according to illustrative embodiments. Combiner 500may be the same or similar to combiner 400 of FIG. 4 and components ofcombiner 500 (e.g. input terminals 501 a-501 h, sensors/sensorinterfaces 5 a-5 d, controller 502, output terminals 503 a-503 b andoutput sensor(s)/sensor interface(s) 504) may be the same or similar tocorresponding components of combiner 400 (e.g. input terminals 401 a-401n, sensors/sensor interfaces 4 a-4 n, controller 402, output terminals403 a-403 m and output sensor(s)/sensor interface(s) 404 a). In someembodiments, combiner 500 may comprise input terminals 501 a-501 h. Eachsensor/sensor interface of sensors/sensor interfaces 5 a-5 d may becoupled to one or more of input terminals 501 a-501 h. Sensors/sensorinterfaces 5 a-5 d may sense the voltage on input terminals 501 a-501 h.Combiner 500 may comprise two or more output terminals 503 a-503 belectrically coupled to a load 505. Output sensor/sensor interface 504may sense the voltage, and/or other parameters, on output terminals 503a-503 b. In some embodiments, the output voltage may be determined byload 505 electrically coupled to output terminals 503 a-503 b.Controller 502 may receive the sensed values of sensors/sensorinterfaces 5 a-5 d and/or output sensor(s)/sensor interface(s) 504. Insome embodiments, controller 502 may switch, or control, switches5Sa-5Sd and may cause input terminals 501 a-501 h to be electricallycoupled in series so that the voltages of input terminals 501 a-501 hwill be added to each other:V_(tot)=V_(501a-b)+V_(501c-d)+V_(501e-f)V_(501g-h)=V_(503a-b).

Reference is now made to FIG. 5B, which shows combiner 500 in a secondmode of operation according to illustrative embodiments. Sensors/sensorinterfaces 5 a-5 d may sense a voltage value on input terminals 501a-501 h. Output sensor(s)/sensor interface(s) 504 may sense thedifferential voltage of output terminals 503 a-503 b. Controller 502 mayreceive the values sensed by sensors/sensor interfaces 5 a-5 d andoutput sensor(s)/sensor 504. The voltage between output terminals 503a-503 b may be a voltage determined by load 505, e.g., a voltage of 700Vor any other voltage. In some embodiments, the voltage may be sensed ateach one of pairs of input terminals 501 a-501 d (which again may be,e.g., 700V or any other voltage). Controller 502 may switch switches5Sa-5Sd at input terminals 501 a-501 h to electrically couple inputterminals 501 a-501 h in parallel. When electrically coupling inputterminals 501 a-501 h in parallel, a common voltage may be appliedbetween each pair of input terminals, and a combined current (i.e. thesum of the currents flowing through input terminals 501 a-501 d) may betransferred to output terminals 503 a-503 b.

Reference is now made to FIG. 5C, which shows combiner 500 in a thirdmode of operation according to illustrative embodiments. In some cases,the voltage and current values on input terminals 501 a-501 h and outputterminals 503 a-503 b may vary. For example, output sensor(s)/sensorinterface(s) 504 may sense that the output voltage on output terminals503 a-503 b is 700V. Sensor(s)/sensor interface(s) 5 a may sense thatthe voltage on input terminals 501 a-501 b is 300V, whilesensor(s)/sensor interface(s) 5 b may sense that the voltage on inputterminals 501 c-501 d is 500V. Sensor(s)/sensor interface(s) 5 c maysense that the voltage on input terminals 501 e-501 f is 500V, whilesensor(s)/sensor interface(s) 5 d may sense that the voltage on inputterminals 501 g-501 h may be 300V. In this example, controller 502 mayreceive the values sensed by sensors/sensor interfaces 5 a-5 d, andaccordingly may electrically couple pairs of input terminals 501 a-501 band 501 c-501 d in a series configuration and electrically couple pairsof input terminals 501 e-501 f and 501 g-501 h in a series configurationcreating two points with a differential voltage between them of 700V inthis example. As well as electrically coupling two pairs of inputterminals in series, controller 502 may electrically couple inputterminals in a parallel configuration, using electrical links 504 a and504 b with a voltage of 700V where input terminals 501 a and 501 e maybe coupled to electrical link 504 a, and input terminals 501 d and 501 hmay be coupled to electrical link 504 b. Output terminals 503 a-503 bmay be electrically coupled to links 504 a-504 b. Controller 502 mayelectrically couple, in series, pairs of input terminals 501 a-501 b and501 e-501 f, as well as electrically couple, in series, pairs of inputterminals 501 c-501 d and 501 g-501 h (not shown). After electricallycoupling pairs of input terminals 501 a-501 b and 501 c-501 d in seriesand pairs of input terminals 501 e-501 f and 501 g-501 h in series,controller 502 may electrically couple the two sets of pairs of inputterminals in parallel. By electrically coupling pairs of input terminals501 a-501 b and 501 c-501 d in series, and pairs of input terminals 501e-501 f and 501 g-501 h in series, controller 502 may create a balancedvoltage between output terminals 503 a-503 b and input terminals 501a-501 h according to output sensor(s)/sensor interface(s) 504 incombiner 500.

Reference is now made to FIG. 5D, which shows combiner 500 in a fourthmode of operation according to illustrative embodiments. In some casesthe voltage and/or current at input terminals 501 a-501 b may bedifferent than the voltage and/or current at input terminals 501 c-501d, 501 e-501 f and/or 501 g-501 h. When trying to draw the maximumamount of power from input terminals 501 a-501 h, controller 503 maycouple one or more pairs of input terminals 501 a-501 h in series, oneor more pairs of input terminals 501 a-501 h in parallel, and in somecases controller 503 may couple inputs 501 a-501 h in a combinedconfiguration (some pairs of the input terminals in series and somepairs of the input terminals in parallel), such as the configurationshown in FIG. 5D. Under certain conditions, one or more input terminals501 a-501 h may be more harmful than useful with regard to the amount ofpower combiner 500 may transfer from input terminals 501 a-501 h tooutput terminals 503 a-503 b. For example, sensor(s)/sensor interface(s)5 a may sense a voltage value of 400V and current value of 10 A at inputterminals 501 a-501 b. Sensor(s)/sensor interface(s) 5 b may a sense avoltage value of 10V and current value of 2 A at input terminals 501c-501 d. Sensor(s)/sensor interface(s) 5 c may sense a voltage value of150V and a current value of 20 A at input terminals 501 e-501 fSensor(s)/sensor interface(s) 5 d may sense a voltage value of 250V anda current value of 20 A at input terminals 501 g-501 h. It should benoted that all voltage and current values mentioned throughout thisdocument are merely examples, and any other voltage and current valuesmay be used or measured in any of the embodiments. Controller 502 may beconfigured to maximize the amount of power extracted from inputterminals 501 a-501 g and therefore may switch the switches at inputterminals 501 a-501 h as follows: input terminals 501 e-501 f and 501g-501 h may be electrically coupled in series, input terminals 501 a-501b may be electrically coupled in parallel to the series configuration ofinput terminals 501 e-501 h, and input terminals 501 c-501 d may beshorted together. In this configuration, input terminals 501 a-501 h maytransfer power to output terminals 503 a-503 b with a value of:V_(tot)=V_(501a-b)∥(V_(501e-f)+V_(501g-h))=400V andI_(tot)=I_(501a)+(I_(501g)=I_(501e))=30 A (for example), which gives thepower value of: P_(503a-b)=V_(tot)×I_(tot)=12,000 W (for example). Insome embodiments, combiner 500 may be placed as part of a power system.One or more power generators may be coupled to combiner 500 at one ormore input terminals 501 a-501 h. Output terminals 503 a-503 b may beelectrically coupled to load 505, which in some embodiments, may be apower converter connected to a grid, a storage device, an electricalvehicle, etc. Load 505 coupled to output terminals 503 a-503 b maydetermine the voltage of output terminals 503 a-503 b. The voltage ofoutput terminals 503 a-503 b may determine the voltage on links 504a-504 b which may determine the voltage on input terminals 501 a-501 h.Coupled to input terminals 501 a-501 h may be power generators (shown inFIGS. 1-3 ), which may have a preferred operating point, such as apreferred voltage or current which may supply more power to inputterminals 501 a-501 h rather than a different operating point which maysupply less power to input terminals 501 a-501 e. One way for controller502 to electrically couple input terminals 501 a-501 d in a moreefficient way with regard to setting a more efficient operating point oninput terminals 501 a-501 d is to check, learn, and/or otherwisedetermine what an effective operating point (e.g., the most effectiveoperating point) of each power generator coupled to input terminals 501a-501 h is. In some embodiments, coupled to outputs 503 a-503 b may be apower device configured to perform power point tracking, which maycomprise tracking the operating point of the power flowing from inputterminals 501 a-501 h through combiner 500 and out of output terminals503 a-503 b. Controller 502 may determine (e.g., “learn”) what is apreferred (e.g., most effective) operating point for each powergenerator coupled to input terminals 501 a-501 d by electricallycoupling one pair of input terminals 501 a-501 h at a time to outputterminals 503 a-503 b and shorting or disconnecting the other inputterminals while doing so. For each pair of pairs of input terminals 501a-501 h that is electrically coupled to output terminals 503 a-503 b,the power device electrically coupled to output terminals 503 a-503 bmay determine (e.g. search for) a preferred operating point. The searchmay be done by selecting a group of voltages between 0V and V_(OC),applying each voltage in the group to the output terminals and sensingthe output current corresponding to the applied voltage, and calculatingthe amount of power generated by the applied voltage and the sensedcurrent flowing from the pair of input terminals of input terminals 501a-501 h coupled to output terminals 503 a-503 b. The preferred operatingpoint may be selected to correspond to the voltage that outputs the mostpower. The preferred operating point found of the coupled pair of inputterminals 501 a-501 h to outputs 503 a-503 b may be saved by controller502.

In some embodiments (e.g., as shown in FIG. 2 and FIG. 3 ), one or morepower devices may be electrically coupled to one or more of inputterminals 501 a-501 h. Power devices coupled to input terminals 501a-501 h may apply power point tracking to power generators to increase(e.g., maximize) power harvesting of the power generators. In someembodiments, power devices may convert power from a first voltage andfirst current level to a second voltage and second current level.Converting power from a first voltage and first current level to asecond voltage and second current level may be carried out at anefficiency rate that may depend on the conversion ratio of the voltagelevel. Controller 502 may electrically couple one or more inputterminals of input terminals 501 a-501 h in series, parallel, or acombined configuration of series and parallel. The configuration chosenby controller 502 may be based on the efficiency at different conversionratios of power devices coupled to input terminals 501 a-501 h.

In some embodiments, output terminals 503 a-503 b might not be connectedto a load and/or might not have a set voltage level between them. One ormore of input terminals 501 a-501 h may be electrically coupled to oneor more power generators that may create a voltage across each pair ofinput terminals 501 a-501 h. Sensors 5 a-5 d may sense a differentialvoltage on pairs of input terminals 501 a-501 h and provide the sensedvalue to controller 502. Output terminals 503 a-503 b may be coupled toinput terminals 501 a-501 h. Controller 502 may be configured to limitand/or reduce the voltage across output terminals 503 a-503 b, forexample, to comply with a regulatory maximum output voltage. Forexample, upon detecting an output voltage above an allowed limit orabove a preferred operating point, controller 502 may reduce the voltageacross output terminals 503 a-503 b by electrically coupling some or allof input terminals 501 a-501 h in parallel, which may reduce the numberof serially-connected power generators coupled to input terminals 501a-501 h. In another example, the controller 502 may short one or morepower generators coupled to input terminals 501 a-501 h, which mayprevent the rising of the voltage on output terminals 503 a-503 b.

In some embodiments, controller 502 may be configured to limit thevoltage on input terminals 501 a-501 h. For example, controller 502 maybe configured to limit the total voltage across each pair of inputterminals 501 a-501 h to under a threshold, for example, 500V. Forexample, input terminals 501 a-501 b may have a voltage differential of300V and input terminals 501 c-501 d may have a differential of 400V andmay be connected in series to input terminals 501 a-501 b (e.g. as shownin FIG. 5A). Controller 502 may switch switches 5Sa-5Sd, which mayelectrically couple pairs of input terminals 501 a-501 b and 501 c-501 din parallel (forcing pairs of input terminals 501 a-501 b and 501 c-501d to have a common voltage, which may change associated powergenerators' operating points), or may short either pair of inputterminals 501 a-501 b or pair of input terminals 501 c-501 d to reducethe total voltage drop across input terminals 501 a-501 d.

Reference is now made to FIG. 5E, which shows combiner 500 coupled topower generator 506 according to illustrative embodiments. Powergenerator 506 may comprise PV panels 506 a-506 d. PV panels 506 a-506 dmay be electrically coupled, for example, in series. In someembodiments, the connection between PV panels 506 b and 506 c maycomprise switch S506. Power generator 506 may be electrically coupled tocombiner 500 at input terminals 501 a and 501 d. Power generator 506 maycomprise outputs coupled to input terminal 501 b and 501 c. Switch S506may be configured to electrically couple PV panel 506 b to PV panel 506c, or electrically couple PV panel 506 c to input terminal 501 c. Switch5Sb may be configured to electrically couple input terminal 501 b topower link 504 a or uncouple input terminal 501 b from power link 504 a.In some embodiments, controller 502 may be configured to limit thedifferential voltage between two points in a power generator. One way tolimit the differential voltage on a power generator string of PV panelsis to divide the string (e.g. by controller 502 operating one or moreswitches) into more than one part. For example, PV panels 506 a-506 d ofPV generator 506 may each be under a differential voltage of 50V, and anentire string may have a differential voltage string of 200V. Controller502 may be configured to limit the voltage of any power generator to150V, and controller 502 may switch switches S506 and 5Sb so that PVpanel 506 b is electrically coupled to power link 504 b and uncoupledfrom PV panel 506 c, as well as electrically coupling PV panel 506 c tolink 504 a through input terminal 501 c in such a way that the string ofpanels may be divided into two separate strings parallel to each other.Another way to limit the voltage is to bypass one of the differentsections of the power generator string, for example by shorting inputterminals 501 c and 501 d, as well as electrically coupling inputterminal 501 b to power link 504 b.

Reference is now made to FIG. 5F, which shows a power system 510according to illustrative embodiments. Power system 510 may comprisecombiner 500, power strings 507 a-507 b and load 505. Combiner 500 maybe electrically coupled to power strings 507 a-507 b at input terminals501 a-501 d, and may be electrically coupled to load 505 at outputterminals 503 a-503 b. In some embodiments, power strings 507 a-507 bmay include a string of power generators 506 a-506 j where one or moreof power generators 506 a-506 j in the string is coupled to a powerdevice 509 a-509 j. Power devices 509 a-509 j may be the same or similarto power devices 202 a-202 n of FIG. 2 . For example, power string 507 amay include power generators 506 a-506 e where each power generator ofpower generators 506 a-506 e is coupled to a power device of powerdevices 509 a-509 e. Power devices 509 a-509 j may be configured tobypass and/or adjust the voltage and/or current to a coupled powergenerator of power generators 506 a-506 j. Bypassing a power generatorof power generators 506 a-506 j may include short-circuiting the outputterminals of one of power devices 509 a-509 j coupled to the powergenerator of power generators 506 a-506 j, and/or disconnecting theinput terminals of the power device of power devices 509 a-509 jconnected to a respective power generator of power generators 506 a-506j.

Combiner 500 may include sensor(s) 508. Sensor(s) 508 may be configuredto measure values of electrical parameters and/or physical parameters oninput terminals 501 a-501 d. Electrical parameters may include voltage,current, power, etc., and physical parameters may include pressure,temperature humidity, etc. Controller 502 may be configured to receivethe measured values from sensor(s) 508. According to the measured valuesmeasured by sensor(s) 508, controller 502 may signal one or more ofpower devices 509 a-509 j to bypass and/or adjust the voltage and/orcurrent on the corresponding power generators of power generators 506a-506 j coupled to the one or more of power devices 509 a-509 j.Signaling one or more of power devices 509 a-509 j may include sending a“disable” or “adjust” signal or may include stop sending a “keep alive”signal, where the one or more of power devices 509 a-509 j areconfigured to disable or adjust the voltage and/or current on the powergenerators after not receiving a “keep alive” signal for a period oftime (e.g., 1 second, 5 seconds, 10 seconds). In some embodiments,controller 502 may be configured to transmit the measured values sensedby sensor(s) 508 to load 505, and load 505 may be configured to signal adisable and/or adjust signal, or stop sending a “keep alive” signal toone or more of power devices 506 a-506 j. The signal to power devices509 a-509 j may be transmitted using, for example, a wirelesscommunication device, a power line communications (PLC) device, anacoustic communication device and/or a designated communication line.

Sensor 508 may be configured to measure values of electrical and/orphysical parameters on any of input terminals 501 a-501 d with relationto one or more reference points. For example, sensor 508 may measure avoltage between a first input terminal (e.g., 501 a) and a second inputterminal (e.g., 501 b or 501 d), a first input terminal (e.g., 501 a)compared to a ground or neutral reference point. In some embodiments,controller 502 may receive more than one measurement from sensor(s) 508and may compute a sum or average value of the measurements. In someembodiments controller 502 may be configured to signal one or more ofpower devices 509 a-509 j in a scenario where one or more of themeasurements sensed by sensor(s) 508 is higher or lower than a computedaverage by more than a certain threshold, and/or if a difference betweentwo measurements is more than a certain threshold. In some embodiments,sensor(s) 508 may measure temperature at a plurality of points, and in acase where on or more of the temperatures is over a set temperature,controller 502 may be configured to signal power devices 509 a-509 j todisable or adjust/limit the voltage and/or current on power generators506 a-506 j.

Reference is now made to FIG. 6 , which shows a power system 600according to illustrative embodiments. Power system 600 may comprisepower generators 601 a-601 n, power devices 602 a-602 n which mayperform PPT on one or more of power generators 601 a-601 n, combiner 603which may be the same or similar to combiner 500 of FIG. 5A-5AD, andsystem power device 604 which may be configured to connect to the grid.In some embodiments, power system 600 may comprise a safety mechanism606. Safety mechanism 606 may be integrated in or mounted on systempower device 604, or may be a standalone mechanism. Safety mechanism 606may be triggered automatically, for example when a voltage level incombiner 500 is above a threshold level, or when a current or currentssensed by sensors/sensor interfaces 5 a-5 d are different from thecurrent sensed by output sensor(s)/sensor interface(s) 504. Thisdifference in current may indicate that there is a leakage in combiner500. In some embodiments, safety mechanism 606 may comprise a mechanicalswitch designed to be manually activated, and which may cause powergenerators to be disconnected from combiner 500. When the mechanicalswitch is activated, safety mechanism 606 may be switched from a“regular mode” where combiner 500 is transferring power from inputterminals 501 a-501 d to output terminals 503 a-50b, to a “safe mode”where combiner 500 does not transfer power from input terminals 501a-501 d to output terminals 503 a-503 b. For example, the mechanicalswitch may be activated when there is a fire, and, because of the fire,it may be desirable to disconnect the power generators from the combiner500. Safety mechanism 606 may be configured to signal and/or communicatewith system power device 604 and/or combiner 603, and may instruct thesystem power device 604 and/or combiner 603 to enter a safe mode. Systempower device 604 and/or combiner 603 may comprise a receiving deviceand/or a communication device configured to receive a signal and/orcommunicate with safety mechanism 606. A safe mode may include, forexample, lowering the voltage input to system power device 604,disconnecting system power device 604 from the grid, and/ordisconnecting system power device 604 from combiner 603. The safe modemay be configured to different settings. For example, settings of thesafe mode may be configured based on which country the device is locatedin and/or whether the device is located in an area controlled by safetyregulations. In some embodiments, system power device 604 may beconfigured to signal combiner 603 after receiving a “go into safe mode”signal from safety mechanism 606. Safe mode in power system 600 mayinclude system power device 604 signaling combiner 603 to lower thevoltage at combiner's 603 output terminals, to lower the voltage atcombiner's 603 input terminals, to lower the current at combiner's 603output terminals, to lower the current at combiner's 603 inputterminals, and/or to disconnect input terminals of combiner 603 and/oroutput terminals of combiner 603. In some embodiments, safety mechanism606 may comprise a safety button, a switch, a screen, and/or a voicerecognition system. In some embodiments, safety mechanism 606 maycomprise an automated system configured to measure certain values suchas voltage, current, heat, hermeticity, humidity, etc., and send a “gointo safe mode” signal if the measured values are above or beneath acertain threshold. Safety mechanism 606 may transmit signals using a PLCdevice (or other wired communication device), wireless communicationdevice and/or an acoustic communication device. Safety mechanism 606 maybe mounted on or housed in system power device 604, mounted on anaccessible wall, part of a user interface on a mobile accessory separatefrom power system 600, etc.

In some embodiments, power system 600 may cause display of a userinterface (UI) 605 on a video display device such as a computer screenof a computer that is part of, or communicatively coupled with, powersystem 600. UI 605 may be used to configure various aspects of the powersystem 600. UI 605 may display monitored values and states of powersystem 600, such as level of power being harvested from powergenerators, voltage and current values in system 600, temperature, time,and/or weather forecast etc. UI 605 may use a PLC device (or other wiredcommunication device), wireless communication device and/or an acousticcommunication device to receive monitored values from differentcomponents of power system 600 such as power generators 601 a-601 n,power devices 602 a-602 n, combiner 603, system power device 604 and/orsafety mechanism 606. UI 605 may gather monitored data and display thedata to a user. In some embodiments, UI 605 may provide the user with ameans for controlling power system 600, for example, UI 605 may signalcombiner 603 to disconnect one of power generators 601 a-601 n, go intoa safe mode and/or change voltage or current levels.

Although FIG. 6 illustrates power devices 602 a-602 n as being coupledto the power generators 601 a-601 n and the combiner 603, in someembodiments, power devices 602 a-602 n may be integrated in powergenerators 601 a-601 n. In some embodiments, there may be more than onepower device in one or more power generators 601 a-601 n. In someembodiments, one or more power devices 602 a-602 n may be betweencombiner 603 and system power device 604. In some embodiments, one ormore power devices of power devices 602 a-602 n may be positioned incombiner 603 or may be part of system power device 604.

Reference is now made to FIG. 7A, which shows a flow chart of a method700 a, which may be used for transferring power from power generators ina power system to an output of a combiner according to illustrativeembodiments. Method 700 a may be carried out by one or more controllers(e.g., computer processors) that are part of or operatively attached toone or more components of a power system, such as any of the powersystems described in this document. For example, method 700 a may becarried out with regard to power system 600 comprising combiner 603,power devices 602 a-602 n and power generators 601 a-601 n. In step 701of method 700 a, a controller (e.g. coupled to combiner 603) in thepower system may check if the output voltage of the combiner is set ordetermined by a load and/or a power converter coupled to the outputterminals of the combiner. If the combiner's output terminals' voltageis determined, in step 702 power devices in the power system may try tofind and/or set an operating point for the power generators using apower point tracking method. The power point tracking method for a powergenerator may comprise using a lookup table where there may be a certainlookup table used for a range of temperatures, and the lookup table mayindicate an appropriate current for a given voltage, and/or may indicatean appropriate voltage for a given current. An operating point may befound using impedance matching. An operating point may be found in adynamic search (e.g. “perturb and observe”) where, for example thesearch for an appropriate operating point at which to operate thecorresponding power generator may be changed and the power value beforethe change and after may be compared. This process of changing voltageand/or current, and measuring the resulting power value, may be repeateduntil an appropriate operating point is found.

After finding and/or setting operating points for the power generators,the combiner's pairs of input terminals, which may be coupled to thepower generators and/or the power devices, may have different values ofelectrical parameters such as voltage, current and power flowing throughthem. The values may vary depending on the conversion ratio in the powerdevices and/or the set voltage or current on the input of the combiner.The controller coupled to the combiner in step 703 may try to matchbetween the different pairs of input terminals, to transfer as muchpower as possible or as much power as wanted from the pairs of inputterminals to the outputs of the combiner.

In an embodiment where the output voltage is not determined by a load,the controller may carry out step 703 without having a desired operatingpoint of the power generators. For example, if the method 700 aproceeded from step 701 to step 703 because no output voltage wasdetermined, the controller may carry out step 703 without having adesired operating point of the power generators. After matching thevalues of the electrical parameters in step 703, the combiner maytransfer the power from the pairs of the input terminals of the combinerto the output terminals at step 704. Method 700 a may restart aftercompleting step 704. If the power system is shut off or disconnected,method 700 a may stop or pause after step 704.

Reference is now made to FIG. 7B which shows a flow chart of a method700B for switching switches at the combiner's pairs of input terminalsand electrically coupling the pairs of the input terminals of thecombiner according to illustrative embodiments. Method 700 b may becarried out by one or more controllers (e.g., computer processors)similar to or the same as the controller(s) of method 700 a, and whichmay be part of or communicatively coupled with any of the power systemsdescribed in this document. Method 700 b may be an example of how toperform step 703 of method 700 a. The initial status of the power systemmay have “n” power generators coupled to the combiner. The powergenerators coupled to the combiner may be different power generatorsfrom each other and/or operating under different conditions. In someembodiments, the power system may have one kind of power generators,e.g. photovoltaic panels, which may operate under different and varyingconditions (e.g., two PV panels in a single system may receive differentlevels of solar irradiance, or be cooled by different wind strength). Instep 705, the controller may divide the pairs of input terminals of thecombiner into “m” number of groups. The division may be according tophysical location and/or according to sensed parameter values (voltage,current and power, type of power generator, etc.) at the inputterminals. After dividing the pairs of input terminals into “m” groups,the method may include taking each one of the “m” groups and dividing itinto “m” sub-groups and so on. Step 705 may end when each group orsub-group has “k” pairs of input terminals or less. When reaching “k”pairs of input terminals in each group or sub-group, at step 706 thecontroller may select a connectivity configuration and electricallycouple the different pairs of input terminals in each one of thesub-groups. The controller may select a parallel, series, or a combined(parallel and series) connectivity configuration and electrically couplethe pairs of input terminals according to the configuration. Thecoupling according to the selected input terminals connectivityconfiguration may be performed by the controller switching switches atthe input terminals of the combiner. After electrically coupling eachone of the input terminals in each sub-group, at step 707 the controllermay check if the connectivity of the inter-group (i.e. the group ofsub-groups) has been selected and executed (e.g., implemented). If theconnectivity of the inter group has not been selected and/or executed,the controller may select a connectivity configuration for theinter-group and may electrically couple the sub-groups according to theconfiguration. If the inter-group connectivity has been selected and/orexecuted, all connectivity configurations of the input terminals,sub-groups and groups have been selected and electrically coupled,meaning the method 700B has finished at step 708.

Reference is now made to FIG. 7C, which shows a flow chart of a method700C for determining a configuration for electrically coupling a groupof inputs to a combiner according to illustrative embodiments. Method700C may be carried out by a controller similar to or the same as thecontroller of method 700B, which may be configured in the same manner asfor the other methods described herein, and which may be implemented inany of the power systems described herein. The controller of method 700Cmay select a configuration of connectivity between two or more pairs ofinput terminals, sub-groups or groups of input terminals. A couplingconfiguration for two or more pairs of input terminals, sub-groups, orgroups may be determined according to a comparison between values ofelectrical parameters such as voltage, current and/or power of eachpotential configuration. In step 709, the controller may electricallycouple (e.g. by operating switches) the different pairs of inputterminals, sub-groups or groups in parallel. In step 710 the controllermay measure the values of the electrical parameters in the parallelconfiguration. In step 711, the controller may change the configurationbetween the pairs of input terminals, sub-groups or groups from parallelto series. After electrically coupling the pairs of input terminals,sub-groups or groups in series, step 712 may comprise measuringelectrical parameters of the series configuration. After collecting dataand values of measured parameters from both a parallel and a seriesconfiguration, at step 713 the values of the electrical parametersbetween the different configurations may be compared. According to theresult of the comparison, the controller may determine, in step 714, howto electrically couple each group of inputs to other groups and to thecombiner. For example, the configuration that maximizes power output maybe selected.

Referring to methods 700 a-700 c, while these methods may be carried outin any of the power systems described herein, a particular example forcarrying out methods 700 a-700 c together may also be as follows. Apower system may have eight power generators (or any other number ofpower generators). Each one of the eight power generators may beelectrically coupled to a power device configured to perform PPT andfind an appropriate operating point for a corresponding power generator.The eight power devices may be electrically coupled to eight pairs ofinput terminals of a combiner. The combiner may have two outputs coupledto a storage device with a set voltage of, e.g., 400V. The power devicesconnected to the power generators were able to find an appropriateoperating point for each one of the power generators. In this particularexample, it will be assumed that the appropriate operating points foundand set by the power devices are as follows.

Operating point Power generator Voltage (V) Current (A) Power (W) Number1 100 10 1000 Number 2 100 10 1000 Number 3 100 10 1000 Number 4 100 101000 Number 5 200 5 1000 Number 6 200 5 1000 Number 7 200 5 1000 Number8 200 5 1000

The next step after finding and setting the operating points of powergenerators may be to match power devices according to the voltage andcurrent values of the corresponding power generators. According tomethod 700 b, the initial state may be eight pairs of inputs to thecombiner, two from each power device. The controller coupled to thecombiner may be configured to divide the eight pairs of input terminalsinto two groups. The controller may be configured to stop dividing thegroups into two when each group or sub-group may have two pairs of inputterminals or less. Therefore, the controller may divide the pairs ofinput terminals into two groups, where each group has two sub-groups oftwo pairs of input terminals, as shown by way of example below.

Power generator Sub-groups Groups Number 1 Sub-group 1 Group 1 Number 2Number 3 Sub-group 2 Number 4 Number 5 Sub-group 3 Group 2 Number 6Number 7 Sub-group 4 Number 8

After dividing the pairs of input terminals into groups and sub-groups,the controller may select a connectivity configuration for thesub-groups. In some embodiments, the power devices may convert the powerthat flows through them. The power devices may have an efficiency ratingfor each voltage conversion ratio. The controller may try to connectpower device such that the power devices operate at a high-efficiencyvoltage conversion ratio. The controller may couple power generators 1and 2 in series, power generators 3 and 4 in series, power generators 5and 6 in parallel and power generators 7 and 8 in parallel. Sub-groups1-4 may have, for example, the following electrical parameter values:

Sub-group Voltage (V) Current (A) Power (W) Sub-group 1 100 20 2000Sub-group 2 100 20 2000 Sub-group 3 100 20 2000 Sub-group 4 100 20 2000

After selecting a connectivity configuration and electrically couplingthe sub-groups of power generators, the controller may check if thesub-groups are electrically coupled to each other. The controller mayelectrically couple sub-groups 1 and 2 in series and sub groups 3 and 4in series. Groups 1 and 2 may have, for example, the followingelectrical parameter values:

Group Voltage (V) Current (A) Power (W) Group 1 200 20 4000 Group 2 20020 4000

The controller may electrically couple group 1 and group 2 in seriesbringing the electrical parameters of the combiner inputs to 400V, 20 A,and 8000 W, transferable to the combiners output.

In some embodiments, the controller may adjust the conversion ratios ofone or more of the power devices in order to find a connectivityconfiguration suitable for the output voltage, which may be determinedby the storage coupled to the output terminals of the combiner.

1. An apparatus comprising: a plurality of input terminals configured toreceive harvested power from a plurality of power devices; a pluralityof output terminals configured to provide output power based on theharvested power received by the plurality of input terminals; aplurality of switches coupled to the plurality of input terminals; and acontroller configured to control the plurality of switches to set, basedon one or both of voltages or currents of at least some of the pluralityof input terminals, a coupling configuration of the plurality of inputterminals, wherein the coupling configuration comprises at least some ofthe plurality of input terminals being connected in series and at leastsome of the plurality of input terminals being connected in parallel. 2.The apparatus of claim 1, wherein each power device of the plurality ofpower devices comprises a direct-current to direct-current (DC/DC)converter and is configured to harvest power of a corresponding powergenerator, of a plurality of power generators, using power pointtracking.
 3. The apparatus of claim 2, wherein the power point trackingcomprises maximum power point tracking.
 4. The apparatus of claim 2,wherein at least one of the plurality of power generators comprises atleast one of the following: a photovoltaic generator, a fuel cell, awind turbine, a hydro-turbine, or a supercapacitor.
 5. The apparatus ofclaim 1, wherein the controller is further configured to set a powerpoint tracking operating point for at least one of the plurality ofpower devices.
 6. The apparatus of claim 1, wherein the apparatus isconfigured to output power, based on the harvested power received fromthe plurality of power devices, to a load via the plurality of outputterminals.
 7. The apparatus of claim 6, wherein the plurality of outputterminals are configured to provide the output power having a voltagethat is based on the load.
 8. The apparatus of claim 6, wherein the loadcomprises at least one of an inverter or a storage device.
 9. Theapparatus of claim 1, wherein the controller is configured to set thecoupling configuration based on one or both of voltages or currents ofat least some of the plurality of input terminals.
 10. The apparatus ofclaim 1, wherein the plurality of switches are configured to selectivelyelectrically couple the plurality of input terminals in parallel, inseries or in a combination thereof.
 11. The apparatus of claim 1,wherein the controller is configured to: set the plurality inputterminals to a first coupling configuration; set the plurality of inputterminals to a second coupling configuration; and determine, based on acomparison of an electrical parameter while the plurality of inputterminals are in the first coupling configuration and an electricalparameter while the plurality of input terminals are in the secondcoupling configuration, the coupling configuration of the plurality ofinput terminals.
 12. The apparatus of claim 1, further comprising asafety mechanism configured to be triggered based on at least one of thefollowing conditions: an over-voltage condition, an over-currentcondition, or an over-temperature condition.
 13. The apparatus of claim1, wherein the apparatus is configured to cause one or more of the powerdevices to perform one or more of the following: disabling, enabling, oradjusting the harvested power.
 14. The apparatus of claim 1, furthercomprising a signaling device configured to signal at least one powerdevice of the plurality of power devices, to adjust power input to theapparatus.
 15. A method comprising: measuring, by a controller, a firstelectrical parameter at a first input terminal and a second electricalparameter at a second input terminal, wherein: the first input terminalis coupled to at least a first power generator, wherein the first powergenerator comprises a first power device comprising a firstdirect-current to direct-current (DC/DC) converter, the first powerdevice being configured to harvest power of the first power generatorusing maximum power point tracking, and the second input terminal iscoupled to at least a second power generator, wherein the second powergenerator comprises a second power device comprising a second DC/DCconverter, the second power device being configured to harvest power ofthe second power generator using maximum power point tracking; comparingthe first electrical parameter with the second electrical parameter; andbased on an outcome of the comparing, selectively either connecting thefirst input terminal in series with the second input terminal orconnecting the first input terminal in parallel with the second inputterminal.
 16. The method of claim 15, further comprising setting anoperating point for the first power generator and an operating point forthe second power generator.
 17. The method of claim 15, furthercomprising providing output power to a load, wherein the output power isbased on power received by at least one of the first input terminal orthe second input terminal, and wherein a voltage of the plurality of theoutput power ls is based on the load.
 18. The method of claim 15,further comprising sending, to the at least one first power generator,an instruction to modify a parameter of the at least one first powergenerator.
 19. The method of claim 18, wherein the instruction comprisesan instruction to adjust a voltage output by the at least one firstpower generator.
 20. The method of claim 15, further comprising causingthe at least one first power generator to perform at least one of thefollowing: disabling, enabling, or adjusting the harvested power.